The defendant admitted in a statement to fathering his 28-year-old step-daughter's seven children. An eighth child died shortly after childbirth.

DNA tests have already revealed he fathered his step-daughter's children.

He has denied sexually abusing the children for decades.

Detlef S is an unemployed truck driver from Rhineland village of Fluterschen.

During the trial Tuesday in the western city of Koblen, the judge read aloud a letter by his 18-year-old daughter. It stated that the father first raped her on her 12th birthday after her friends left the party.

"You made my life a living hell," she wrote.

He began raping his twin step-children when they were 4 years old, according to the indictment.

"Later, when his biological daughter, Janine [not her real name] turned 12, he started to rape her once a week, allegedly telling her initially that 'as a father I'm not supposed to do this.' When she was on her period, he would force her to give him oral sex," reported the Guardian.

The case has attracted much attention in Germany, and the father is being called “the German Josef Fritzl,” after the Austrian man who fathered eight children with his daughter locked in a cellar.

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